/*common*/
.left {
    float: left;
}

.right {
    float: right;
}
.center{
    margin: 0 auto;
}
.hidden{
    display: none;
}
.clearfix:before,.clearfix:after {
    content: ".";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}
.clearfix:after{clear:both;}
.clearfix{*zoom: 1;/*ie6,7*/}
.navbar:before, .navbar:after, .navbar-header:before, .navbar-header:after, .navbar-nav-collapse:before, .navbar-nav-collapse:after, .navbar-nav:before, .navbar-nav:after, .row:before, .row:after {
    content: "";
    display: table;
    /*兼容ie8*/
}
.center-f{
     display: -webkit-box;
     display: -webkit-flex;
     display: -ms-flexbox;
     display: flex;
     -webkit-box-orient: vertical;
     -webkit-box-direction: normal;
     -webkit-flex-direction: column;
     -ms-flex-direction: column;
     flex-direction: column;
     -webkit-box-pack: center;
     -webkit-justify-content: center;
     -ms-flex-pack: center;
     justify-content: center;
     -webkit-box-align: center;
     -webkit-align-items: center;
     -ms-flex-align: center;
 }